The 38 Special +P uses the standard 38 Special 1.1551-inch case with .357-inch bullet, but is loaded to higher pressure (18,500 psi versus 17,000) than standard 38 Special ammunition. 38 Special +P ammunition is thus fully interchangeable with 38 Special ammunition. However, it is not necessarily safe to use 38 Special +P in older revolvers and especially revolvers with lightweight aluminum frames. 38 Special +P offers increased velocity and greater energy yield, raising velocity with a 158-grain bullet from 800 to 890 feet per second. With modern bullet designs 38 Special +P is an extremely effective personal defense load.
